A computer model created by researchers at Columbia University's Mailman School of Public Health is tracking and forecasting the growth of Ebola cases in West Africa. Forecasts predicting cumulative infections and deaths six weeks into the future are generated each week and posted online: http://cpid.iri.columbia.edu/ebola.html. Updates are released upon release of new World Health Organization (WHO) data, which are used to train the model prior to forecast.
“During August and early September, the number of Ebola cases grew exponentially,” says Jeffrey Shaman, PhD, associate professor of Environmental Health Sciences at the Mailman School of Public Health, who led the development of the Ebola computer model. “However, in more recent weeks, the outbreak, while still continuing unabated, has not increased as precipitously. While this is encouraging, there are no signs yet that the outbreak is coming under control. The outbreak remains huge and requires an enormous investment and mobilization of resources if it is to be contained. Between 50 and 70 percent of those who get Ebola die from it. By comparison, the 1918 influenza pandemic had a case fatality rate of 2.5 percent.”
Dr. Shaman’s computer model predicts a range of outcomes, including an “improved” scenario, such as would occur if a scale-up in healthcare workers and supplies slows the spread of the disease and a “degraded” scenario, should conditions deteriorate due to factors such as social unrest, more limited healthcare, or virus mutation. “There is a concern that as the virus is transmitted from person-to-person many times, a more transmissible variant will emerge through selection,” he explains.
The project began in early August in conjunction with the Models of Infectious Disease Agent Study (MIDAS) program of the National Institutes of Health through which Dr. Shaman and his team are funded. In times of national emergency, MIDAS is called upon for modeling support by other agencies like the Centers for Disease Control and Prevention (CDC), Health and Human Services and the Biomedical Advanced Research and Development Authority.
In the weeks since Dr. Shaman’s site launched, the CDC and WHO each have published their own Ebola predictions, with the former anticipating 20,000 infections by early November and the latter, as many as 1.4 million cases in Liberia and Sierra Leone by the middle of January.
Says Dr. Shaman, “Modeling and forecasting can help health officials plan for the scope of the outbreak and chart whether intervention, isolation, and containment methods are proving effective at reducing the progression of the disease.”
About Columbia University’s Mailman School of Public Health
Founded in 1922, Columbia University’s Mailman School of Public Health pursues an agenda of research, education, and service to address the critical and complex public health issues affecting New Yorkers, the nation and the world. The Mailman School is the third largest recipient of NIH grants among schools of public health. Its over 450 multi-disciplinary faculty members work in more than 100 countries around the world, addressing such issues as preventing infectious and chronic diseases, environmental health, maternal and child health, health policy, climate change & health, and public health preparedness. It is a leader in public health education with over 1,300 graduate students from more than 40 nations pursuing a variety of master’s and doctoral degree programs. The Mailman School is also home to numerous world-renowned research centers including ICAP (formerly the International Center for AIDS Care and Treatment Programs) and the Center for Infection and Immunity. For more information, please visit www.mailman.columbia.edu.